The use of glycerol monoalkyl ethers in cosmetic compositions is already known in principle. Thus, EP 0 599 433 A1 describes glycerol monoalkylethers containing a C6-18 and preferably a C6-12 alkyl group as a deodorizing component in aqueous or alcoholic deodorant solutions. In DE 100 47 759 A1, C6-18 glycerol monoalkyl ethers are used as antimicrobial components in wet wipes. In this case, too, the shorter chain glycerol monoalkyl ethers are preferred.
By virtue of their ether structure, partial glycerol ethers are stable to hydrolytic or catalytic degradation reaction by acidic antiperspirant salts (aluminium or aluminium/zirconium salts) which is a very important criterion for their use as raw materials in the antiperspirant field.
Hitherto, glycerol ethers have acquired little significance as emulsifiers or consistency factors for cosmetic compositions. In water-containing antiperspirant/deodorant emulsions, fatty alcohols, such as cetearyl, stearyl and behenyl alcohol, fatty acid esters and also triglycerides, such as glycerol monostearate, are normally used as co-emulsifiers or as consistency factors. By virtue of their chemical structure, fatty alcohols and hydroxyfatty acids are stable whereas fatty acid esters and triglycerides, such as glycerol monostearate, are not.
The performance-related development of stable and viscosity-stable, but sensorially agreeable emulsions is a major challenge to the developer, particularly in the antiperspirant/deodorant field. The high salt content, the low pH and the fact that the antiperspirant components dissolved in water give rise to distinctly tacky end properties in the formulation call for new raw material solutions in the field of antiperspirant/deodorant waxes in order to develop improved antiperspirant/deodorant formulations.
Fatty alcohols, such as cetearyl, stearyl and behenyl alcohol, and hydroxyfatty acids, such as 12-hydroxystearic acid, in combination with the polymeric N-acrylic acid amide are frequently used in water-free antiperspirant stick and soft solid formulations (cf. U.S. Pat. No. 5,429,816 A). Systems such as these do not always leave an optimal feeling on the skin after application, even when optimized emollients are used.
Accordingly, the problem addressed by the present invention was to provide an emulsifier or consistency factor which would be suitable for use over a broad range of applications and which, in the field of aqueous o/w emulsions or solid cosmetic compositions and particularly in antiperspirant/deodorant formulations, would lead to stable products with agreeable sensory properties.